There is an organic electroluminescent device that includes a light transmissive first electrode, a second electrode, and an organic light emitting layer provided between the first electrode and the second electrode. There is an illumination apparatus using the organic electroluminescent device as a light source. There is an illumination system that includes a plurality of organic electroluminescent devices and a controller configured to control turning on and off of the plurality of organic electroluminescent devices. The organic electroluminescent device is made to be light transmissive by using a thin-line shaped second electrode in which a plurality of openings are provided, or using a light transmissive second electrode. An improvement in the visibility of a transmission image is desired in such an organic electroluminescent device.